How to create a data summary function? - r

Question

I'm trying to create a function that summarizes several vectors and the prompt is
Write a function data_summary which takes three inputs:\
`dataset`: A data frame\
`vars`: A character vector whose elements are names of columns from dataset which the user wants summaries for\
`group.name`: A length one character vector which gives the name of the column from dataset which contains the factor which will be used as a grouping variable
\`var.names`: A character vector of the same length as vars which gives the names that the user would like used as the entries under “Variable” in the resulting output. This should be set equal to vars by default, so the default behavior is to use the column names from dataset.
The output of the function should be a data frame with the following structure:
Column names of the data frame will be:\
`Variable`\
`Missing`\
The `first` level of the factor group.name\
The `second` level of the factor group.name\
…\
The `kth` level of the factor group.name\
`p-value`
I've set up the code already,
data_summary <- function(dataset,vars,group.name,var.names) {
}
but I'm unsure how to proceed because I do not understand what this is trying to accomplish and what the output should look like. There is an example that shows
#data_summary<-function(dataset, vars,group.name, var.name){}
#example
#data_summary(titanic4, c("survived", "female", "age", "sibsp", "parch", "fare", "cabin"), "pclass")
#data_summary(titanic4, c("survived", "female", "age", "sibsp", "parch", "fare", "cabin"), "pclass", c("Survival rate", "% Female", "Age", "# siblings/spouses aboard", "# children/parents aboard", "Fare ($)", "Cabin"))
But it really did not help me outside of inputting the arguments for the function.

Answer 1

You can use dplyr package for this function. Also I don't know by which functions you want summarise your dataframe, so I use all functions which summary function returns from base package.
My data:
> NewSKUMatrix
# A tibble: 268,918 x 4
LagerID FilialID CSBID Price
<int> <int> <int> <dbl>
1 233 2578 1005 38.3
2 333 2543 NA 61.0
3 334 2543 NA 15.0
4 335 2543 NA 11.0
5 337 2301 NA 71.0
6 338 2031 NA 37.0
7 338 2044 NA 35.0
8 338 2054 NA 36.0
9 338 2060 NA 37.0
10 338 2063 NA 36.0
# ... with 268,908 more rows
Function:
data_summary <- function(data,
variables,
values,
names = NULL) {
if (is.null(x = names)) {
names <- variables
}
data %>%
group_by_at(.vars = variables) %>%
summarise_at(
.vars = values,
.funs = list(
Min. = min,
`1st Qu.` = ~ quantile(x = ., probs = 0.25),
Median = median,
Mean = mean,
`3rd Qu.` = ~ quantile(x = ., probs = 0.75),
Max. = max
)
) %>%
rename_at(.vars = variables,
.funs = ~ names)
}
Output:
data_summary(NewSKUMatrix,
c('LagerID'),
c('Price'),
c('SKU'))
# A tibble: 32,454 x 7
SKU Min. `1st Qu.` Median Mean `3rd Qu.` Max.
<int> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
1 17 39.0 39.0 39.0 39.0 39.0 39.0
2 18 120. 120. 120. 121. 120. 140.
3 21 289. 289. 289. 289. 289. 289.
4 24 37.0 37.0 37.0 45.2 45.2 70.0
5 25 14.0 14.0 14.0 14.0 14.0 14.0
6 55 30.9 30.9 30.9 30.9 30.9 30.9
7 117 26.9 26.9 26.9 26.9 26.9 26.9
8 118 24.8 24.9 24.9 25.1 25.1 25.7
9 119 24.8 24.8 24.9 25.1 25.3 25.7
10 158 104. 108. 108. 107. 108. 108.
# ... with 32,444 more rows